Error: Missing query string MariaDB NodeJS

I have this error every time I try to run a query to DB:

Error: Missing query string

I don't understand what could be wrong with my code, the query is correct I have tested it:

function getChannelCTSize(octopusMac, channelID, adcTicks, callback){
    var queryString = "SELECT Channels.CT_size FROM Channels INNER JOIN Octopus ON Octopus.Id=Channels.Octopus_Id WHERE Octopus.Mac = ? AND Channels.Channel_Id = ?";
    var filter = [octopusMac, channelID];

    var query = mariaDB.query({
        sql: queryString
    }, filter );

    query.on('error', function(err) {
        if (err) {
            console.log(err.code);
            return
        }
    })
        .on('result', function(row) {
            callback(result[0].CT_size, channelID, octopusMac, adcTicks);
        })
        .on('end', function() {
            mariaDB.release();
        });
}

via Rémi